e/o濃度高有刺激性係一回事，植物本身含有allergen又係另一回事
我講個例子
lavender本身已經含有geraniol, linalool, linalylacetate呢啲allergen，唔理之後經咩process最後得出嘅product都係會存在呢啲active chemical components
Lavender induces tranquility too, but it can also cause enough skin irritation that in May 2014 the Swedish Chemicals Agency (SCA) proposed a health warning on lavender products. The European Union is now considering labeling lavender, “May Be Harmful if Inhaled.” More specifically, a lavender allergy is caused by a compound within lavender extract called linalool. Linalool produces lavender’s fragrance and reacts with air to form the skin irritant. The natural extract of a lavender plant contains 20 to 40 percent linalool, depending on the plant variety, and chemists can synthesize linalool at a purity of 97 percent.
就算你以為有鎮靜作用嘅chamomile in its most natural form其實都一樣可以產生allergic reaction
好多人會意識到自己對海鮮牛肉敏感，但係冇乜人會意識到自己可以對植物敏感。如果佢令你生hives，而你又覺得chamomile extract好天然好鎮靜而忽略咗佢咁就大檸樂
